Manufacturer&#39;s joint



June 7, 1966 A. R. CHAPMAN 3,254,827

MANUFACTURERS JOINT Filed Dec. 20, 1963 INVENTOR. A lberl R. Chapman BY i/ 76 M ATTORNEY A United States Patent 3,254,827 MANUFAeTURERs JOINT I Albert R. Chapman, Corning, N.Y., assignor to Corning Glass Works, Corning, N.Y., a corporation of New This application is a continuation-in-part of my copending application S.N. 286,637, filed June 10, 1963.

This invention relates to an improved corrugated carton construction for providing such cartons with a finished aesthetic appearance, and more particularly to an improved manufacturers joint construction on corrugated cartons wherein a single liner flap extends over the raw edge of the manufacturers joint,

In the past, corrugated boxes were primarily utilized as shipping containers. In recent years, however, through the use of improved graphics, the corrugated box has become a consumer package. appeal of such corrugated cartons has been enhanced by the utilization of modern graphic techniques, nothing has been done to eliminate the crude and unsightly rawedged structural configurations inherently produced in the formation of such cartons.

Presently, such cartons are manufactured from a blank having a glue flap at one end, which is secured, by suitable adhesive, to the inner surface of an end panel at the opposite end of the blank. The resulting connection is known as a manufacturers joint. However, the container exhibits the raw corrugated edge of the side panel forming the manufacturers joint, adjacent either a front or rear panel of the carton. Such raw corrugated edge materially detracts from the aesthetic appeal produced by the improved graphics, thus lessening their value in providing an acceptable consumer package.

My invention includes novel structure for forming an improved manufacturers joint wherein the usual glue flap, which is formed integrally with the corrugated board from which the carton is produced, is slit and scored and stripped to form a single liner flap for covering or overlying the raw edge of the manufacturers joint, and an improved method for producing such improved joint.

It thus has been an object of my invention to provide an improved structure for corrugated containers which enhances the aesthetic appeal thereof for utilization as a consumer package.

A further object of my invention has been to provide means for covering or overlying the raw edge of a manufacturers joint on corrugated containers.

An additional object of my invention has been to provide a simple method of forming a flap for overlying the raw edge of a manufacturers joint.

These and other objects of my invention will become more apparent to those skilled in the art from the following disclosure and accompanying drawings in which:

FIG. 1 is a plan view of a blank for forming a corrugated container embodying a hidden maufaoturers joint in accordance with my invention;

FIG. 2 is an enlarged fragmental view in elevation illustrating the positionment of a single liner flap with respect to the raw edge of a manufacturers joint, with the carton in a flattened position such as when storing or warehousing; and

FIG. 3 is an enlarged fragmental view illustrating the single liner flap overlying the raw edge of the manufacturers joint and an inner liner of a side panel abutting the raw edge of a front wall panel when the cart-on is in an assembled position.

Referring now to the drawings, and particularly FIG. 1, a carton blank 11 formed of corrugated board is shown Although the aesthetic having a conventional tab or glue flap 13, a frontwall panel 15, side or end wall panels 17 and 19, and rear wall panel 21, all of which are of known construction in the industry. Although the carton may be provided with any suitable top and bottom closure means, such as the commonly utilized interlocking bottom flaps, or overlying taped or adhesively bound top flaps, tab-locking cover flaps are shown for the purpose of illustration. The top closure means is shown comprising a top flap 23 having a tongue 25, a pair of side flaps 27 and 29, and an inner top flap 31 having a locking tab 33 formed partially therein. In like manner, the bottom closure means is shown comprising a bottom flap 35 having a tongue 37, a pair of bottom end flaps 39 and 41, and an inner bottom flap 43 having a locking tab 45 formed partially therein. The panels 15, 17, 21 and 19 are separated by conventional score lines 47, 49 and 51, respectively. However, the glue fiap or tab 13 is separated from the front panel 15 by means of a slit score 53 formed on an inner surface of the blank 11.

The blank 11, and the resulting carton formed therefrom, may be made of any known type of corrugated board. Although single wall board is shown in FIGS. 2 and 3 for purposes of illustration, it is also possible to utilize a double wall board or triple wall board. The single wall board is shown having an outer liner 55, a corrugating medium 57, and an inner liner 59.

In preparing a single liner flap 13 from tab 13, for hiding or overlying the raw edge of the improved manufacturers joint, inner liner 59 and corrugating medium 57 are slit scored at 53, as mentioned above. The inner liner and corrugating medium may then be easily removed by milling them off with a molding head cutter attachment. The molding head cutter may be easily at tached to presently known gluing machines used to make manufacturers joints, thereby eliminating the need of a separate operation and separate machinery. Upon stripping the inner liner 59 and corrugating medium 57 from the tab 13 by means of the milling operation, the thin, outer, single liner fiap 13' is left extending from the outer liner of panel 15. The improved manufacturers joint is then made by gluing the single liner flap 13' to the outer surface of the outer liner 55 of flap receiving panel 19 so as to overlie the raw edges of such flap receiving panel 19 and front panel 15 thus hiding or concealing the manufacturers joint.

Prior to assembly for use as a carton, the raw edge of the front wall panel and the end wall panel are exposed. After assembly the raw edge of side wall panel 19 abuts and is thereby hidden by the inner surface of the single liner fiap 13'. Simultaneously the raw edge of -front wall panel 15 abuts and is similarly hidden by the inner liner of the side wall panel. My invention thus has hidden two exposed raw edges and rendered them harmless to users of my invention.

The outer liner flap not only materially increases the aesthetic appearance of the resulting carton by overlying the raw edge of the manufacturers joint, but also provides a more secure or stronger joint than that obtained by the conventional glue flap. In the conventional joint wherein the glue fiap forms an adhesive joint on the inside of a carton, the loads normally exerted by the canton on the glue or adhesive forming the joint tend to peel the joint thus setting up tensile forces in the adhesive bond. When an adhesive joint is formed on the outside of a carton, as disclosed by my invention, the loads normally exerted by the carton on the glue or adhesive forming the joint tend to move the adjacent faces of the connector flap and its associated panel across one another in a parallel sliding relationship, thereby placing shear forces on the adhesive. In view of the fact that shear strengths of such adhesive are much higher than their tensile or peel strengths, the improved outside joint of my invention provides increased strength.

In addition, the exposed raw edge of the old type of manufacturers joint, being an abrupt and unfinished edge, was subject to abrasion and peeling thus tending to not only deface the carton but also loosen the joint. With the application of my overlying outer liner flap, which covers and hides the raw edge of the joint with a smooth flowing surface, abrasion is materially reduced thus facilitating the securement of the joint as a permanent fixture. Further, the interior glue flap had a tendency to interfere with the loading of articles within the carton. However with my improved construction this is no longer a problem and the carton is easier to pack, since the conventional glue flap has been eliminated and, accordingly, there is no obstruction within the carton.

Although I have disclosed the now preferred embodiment of my invention, it will be apparent to those skilled in the art various changes and modifications may be made thereto without departing from the spirit and scope of my invention as defined in the appended claim.

I claim:

An improved corrugated carton structure having a simplified manufacturers joint providing structural rigidity which comprises; a plurality of adjacent wall panels formed from a corrugated board having an inner liner, an outer liner, and a corrugating medium therebetween; said wall panels being separated by a plurality of score lines and having end closure means extending along a pair of opposed edges, a flap-receiving panel adjacent one end of said wall panels having an exposed raw edge, a further wall panel adjacent the opposite end of said wall panels also having a raw edge, an outer liner flap extending from the outer liner of said further wall panel and beyond the raw edge thereof; said outer liner flap adhesively secured to the outer liner of said flap-receiving panel with the exposed raw edge of said flap-receiving panel abutting vthe inner surface of the outer liner flap, and with the raw edge of said further wall panel simultaneously abutting the inner liner of said flap-receiving panel to provide a permanent structurally sound manufacturers joint for said wall panels with a finished aesthetic appearance.

References Cited by the Examiner UNITED STATES PATENTS 941,256 11/1909 Jenkins. 1,025,443 5/ 1912 Angier. 1,299,824 4/ 1919 Cullen 22948 1,430,287 9/ 1922 Crowell. 2,985,075 5/1961 Knutsson-Hall 93-36 3,112,855 12/ 1963 Hennessey et al. 3,124,295 3/ 1964 Kauffeld 229--43 3,137,217 6/1964 Elliott 93-36 FRANKLIN T. GARRETT, Primary Examiner.

I. L. KRUTER, Assistant Examiner. 

